KR101839668B1

KR101839668B1 - Apparatus for foot pressure measuring and ground reaction force measuring method using the same

Info

Publication number: KR101839668B1
Application number: KR1020160002152A
Authority: KR
Inventors: 문정환; 심태용; 윤수현; 주수빈
Original assignee: 성균관대학교산학협력단
Priority date: 2016-01-07
Filing date: 2016-01-07
Publication date: 2018-03-19
Also published as: KR20170083186A

Abstract

The present invention relates to a foot pressure measuring apparatus, comprising: a sensor unit provided in an insole shape and having a plurality of sensing positions arranged in a longitudinal direction and a width direction, and a pressure sensor provided at a plurality of sensing positions selected from the sensing positions; And a controller for measuring a pressure value at the sensing position where the pressure sensor is installed and a pressure value based on the pressure value of the pressure sensor by using an interpolation method at a sensing position where the pressure sensor is not located, And a calculation unit for calculating the horizontal surface reaction force based on the calculated vertical surface ground reaction force after calculating the ground surface reaction force so that the pressure sensor is installed on the basis of the pressure value of the portion where the pressure sensor is installed, There is provided a foot pressure measuring device capable of accurately measuring the ground reaction force in the three axial directions by calculating the vertical ground reaction force and calculating the horizontal ground reaction force.

Description

BACKGROUND OF THE INVENTION Field of the Invention [0001] The present invention relates to a foot pressure measuring apparatus,

The present invention relates to a foot pressure measuring apparatus and a surface reaction force measuring method using the same. More particularly, the present invention relates to an insole-type sensor unit having a plurality of pressure sensors, The present invention relates to a foot pressure measuring device capable of calculating a three-axis ground reaction force by calculating a pressure value using a predetermined interpolation method, and a floor reaction force measuring method using the foot pressure measuring device.

In general, foot orthopedic insole is used for the treatment of diseases caused by structural abnormalities of the feet such as flat feet and bodily limbs, weight load such as myelopathy / plantar fasciitis / hammer, foot diseases caused by narrow shoes, prevention of foot necrosis due to diabetes, It is used to relieve the load imbalance caused by arthritis. It is used to shape the insole face considering the foot type and disease of a specific person, protects the lesion site by padding the pad, Catch and treat and prevent the disease.

In order to manufacture such an insole for foot orthodontic treatment, a process of measuring a weight load pressure, i.e., a foot pressure distributed on a specific person's foot is preceded by the fact that, as a result of most foot diseases, Unlike the pressure distribution, pressure is concentrated in a specific region.

Regular foot pressure measurement is a method of measuring the pressure of a unit area sequentially by measuring the foot contact surface using ink or by using a force plate equipped with a plurality of pressure sensors, The measurement result is displayed as a mosaic graph in which the color of the unit area pressure is changed.

However, these measurement results were obtained by walking on a flat plate or a force plate without wearing shoes, and there was a problem in that measurement was possible only for a limited operation due to the limitation of the walking distance.

In addition, even if the insole for correction is manufactured based on the measurement result, there is a problem that the pressure applied to the foot differs from the expected value according to the wearer's shoes.

In addition, the orthopedic insole is manufactured through a variety of processes, such as forming a foot shape of a specific person's foot separately from the measurement of the forefoot pressure, and molding a pattern based on the foot pressure with the insole material. The foot pressure of the shoe heel that is used by inserting the orthopedic insole is changed with time due to the wear of the foot heel, the shape change, and so on, so that the correction effect is remarkably decreased. The insole has a problem in that there is no means for correcting the pressure in response thereto.

Korean Patent Publication No. 10-2014-0090135

SUMMARY OF THE INVENTION The present invention provides a foot pressure measuring apparatus capable of measuring a foot pressure while walking without being influenced by a surrounding environment while wearing a shoe, and a floor reaction force measuring method using the foot pressure measuring apparatus have.

It is another object of the present invention to provide a foot pressure measuring apparatus and a floor reaction force measuring method capable of determining the diagnosis and evaluation of a patient having a musculoskeletal disease through gait analysis by allowing the foot pressure to be measured while wearing a shoe.

The present invention also provides a foot pressure measuring device capable of accurately measuring foot pressure deviations according to gait characteristics of individual patients by enabling measurement of foot pressure in a state of wearing shoes, and a floor reaction force measuring method using the same.

Also, the pressure value of the portion where the pressure sensor is not provided is derived on the basis of the pressure value of the portion where the pressure sensor is installed even in the state of wearing the shoe to calculate the vertical surface ground reaction force and then calculate the horizontal ground surface reaction force, And a foot reaction force measurement method using the foot pressure measurement device.

According to an aspect of the present invention, there is provided an apparatus for measuring foot pressure using a ground reaction force, comprising: a plurality of sensing positions arranged in an insole shape and arranged in a longitudinal direction and a width direction; A sensor unit provided with a pressure sensor at a position; And a controller for measuring a pressure value at the sensing position where the pressure sensor is installed and a pressure value based on the pressure value of the pressure sensor by using an interpolation method at a sensing position where the pressure sensor is not located, And a calculation unit that calculates the floor surface reaction force based on the calculated vertical surface ground reaction force after calculating the ground surface reaction force.

Here, the interpolation method may be a cubic spline interpolation interpolation method.

The sensor unit includes a toe region corresponding to the toe portion and divided into two in the width direction, a front region corresponding to the forefoot region and located rearward of the toe region and divided into three in the width direction, And an insole base member partitioned into a heel region divided into two in the width direction and a midsole region divided into two in the width direction, the pressure sensor being disposed between the front region and the rear region of the insole base material, And may be respectively installed in divided portions.

Further, the pressure sensor located at the divided portion in the same area may be provided so as to be positioned in a straight line in the width direction.

Further, the forward direction ground reaction force GRF _ap (t) of the horizontal direction ground reaction force can be calculated by the following equation.

GRF _ap (t) = GRF _vertical (t) X tanAP _[theta] (t),

,

GRF _vertical (t): vertical ground reaction force,

AP _θ (t): Angle between the vector from the foot to the center of gravity of the body and the vector from the ground to the vertical direction is projected onto the sagittal plane,

T: Stance phase time while the foot touches the ground during walking,

Stride = Key X 0.415

Also, the ground surface reaction force GRF _ml (t) in the direction perpendicular to the advancing direction among the horizontal ground surface reaction force can be calculated by the following equation.

GRF _ml (t) = GRF _vertical (t) X tan ML _? (T),

,

GRF _vertical (t): vertical ground reaction force,

ML _θ (t): The angle between the vector from the foot to the center of gravity of the body and the vector from the ground to the vertical direction is projected onto the frontal plane,

DS: double support time during walking,

T: Stance phase time while the foot touches the ground during walking

A plurality of sensing positions, which are arranged in the longitudinal direction and the width direction, are set, and a pressure sensor (not shown) is disposed at a plurality of sensing positions selected from the sensing positions. Preparing and worn a sensor unit provided with a sensor; A pressure value is measured at a sensing position where the pressure sensor is installed through a pressure sensor of the sensor unit when the sensor unit is worn while wearing the sensor unit and a pressure value is calculated using an interpolation method set at a sensing position where the pressure sensor is not installed Calculating a vertical ground reaction force; And calculating a horizontal ground reaction force on the basis of the vertical ground reaction force.

According to the present invention, there is provided a foot pressure measuring apparatus capable of measuring a foot pressure in a state in which a shoe is worn, and a floor reaction force measuring method using the same.

Also, a foot pressure measurement device capable of determining the diagnosis and evaluation of a patient having a musculoskeletal disease through gait analysis by measuring the foot pressure in a state in which the shoe is worn can be provided, and a floor reaction force measurement method using the foot pressure measurement device is provided.

Also, a foot pressure measuring device capable of accurately measuring a foot pressure deviation according to a walking characteristic of an individual patient by allowing the foot pressure to be measured while wearing a shoe, and a floor reaction force measuring method using the same are provided.

Also, the pressure value of the portion where the pressure sensor is not provided is derived on the basis of the pressure value of the portion where the pressure sensor is installed even in the state of wearing the shoe to calculate the vertical surface ground reaction force and then calculate the horizontal ground surface reaction force, A foot pressure measuring device capable of accurately measuring the repulsive force and a ground reaction force measuring method using the same are provided.

The foot pressure distribution of the normal foot shown in Fig.
2 is a schematic view of an apparatus for measuring foot pressure according to a first embodiment of the present invention,
3 is an enlarged view of the sensor unit,
FIG. 4 is a graph showing the vertical direction ground reaction force measured using the force plate and the vertical direction ground reaction force calculated according to the present embodiment,
FIG. 5 is a diagram showing a vector relationship between the feet and the center of gravity of the body on the side of walking;
Figure 6 is a graph showing the value of _θ AP during time T,
Fig. 7 is a graph showing the forward-direction floor surface repulsion force measured using the force plate and the forward direction floor surface repulsion force calculated according to this embodiment
8 is a diagram showing a vector relationship between the feet and the center of gravity of the body on the front face according to the walking,
9 is a graph showing the value of ML _? During the time T,
FIG. 10 is a graph showing vertical ground surface reaction force measured in the forward direction measured by using force plates and vertical ground surface reaction force in the forward direction calculated according to the present embodiment.
11 is a flowchart showing a method of measuring the floor reaction force using the foot pressure measuring apparatus of the present invention

Prior to the description, components having the same configuration are denoted by the same reference numerals as those in the first embodiment. In other embodiments, configurations different from those of the first embodiment will be described do.

Hereinafter, a foot pressure measuring apparatus according to a first embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a schematic view of a foot pressure measuring apparatus according to a first embodiment of the present invention, and FIG. 3 is an enlarged view of a sensor unit.

Referring to FIGS. 2 and 3, the apparatus for measuring foot pressure according to the first embodiment of the present invention includes a sensor unit 10 and a calculation unit 20.

The sensor unit 10 includes an insole base material 11 and a plurality of pressure sensors 12 installed on the insole base material 11.

The insole base material 11 is an insole used for ordinary shoes or the like and is divided into a toe region, a fore and aft region, a middle region, and a heel region according to a portion corresponding to a foot.

The toe region is located at the frontmost position, the front region is located behind the toe region, the middle region is located behind the front region, and the heel region is located at the rear end. This segmentation is an area according to anatomical criteria.

The toe region, the middle region, and the heel region are each divided into two in the width direction, and the entire region is divided into three in the width direction.

Further, the insole base material 11 is set to a plurality of sensing positions at positions where the pressure sensor 12 is installed in the longitudinal direction and the width direction.

At least one of the sensing positions located in the divided portions of the respective regions is selected and installed in the pressure sensor 12, and the measured pressure value is transmitted to the calculation unit 20. [ In the present embodiment, the pressure sensors 12 are provided for each of the divided parts, and a total of nine pressure sensors 12 are installed.

Further, the pressure sensor 12 located at the divided portion in the same area is provided so as to be positioned in a straight line in the width direction.

The calculation unit 20 includes a first calculation unit 21 and a second calculation unit 22. The first calculation unit 21 receives the measured pressure value from the pressure sensor 12 and calculates a pressure at a sensing position where the pressure sensor 12 is not installed by a predetermined interpolation method based on the received pressure value (GRF _vertical (t)) in the vertical direction is calculated by deriving the value.

In this case, the set interpolation method is a cubic spline interpolation method which interpolates using a cubic polynomial spline. The cubic spline interpolation method is applied to each of the width direction and the longitudinal direction of the insole base material, The pressure value of the sensing position can be calculated.

For example, referring to FIG. 3, the pressure value at the sensing position is measured by each of the pressure sensors 12 divided into two parts to the left and right of the toe area, and the pressure value at the sensing position where the pressure sensor 12 is not installed is measured The pressure value at all the sensing positions corresponding to the toe region can be derived by deriving using the cubic spline interpolation method using the applied pressure value.

In the same way, pressure values are derived at all sensed positions of the fore, middle, and heel regions, and then the pressure values of all sensed positions are summed to calculate the vertical surface repulsion.

Although the cubic spline interpolation method is used in this embodiment, other interpolation methods may be set.

FIG. 4 is a graph showing the vertical ground reaction force measured using a force plate and the vertical ground reaction force calculated according to the present embodiment.

As shown in FIG. 4, it can be seen that the vertical ground reaction force (dotted line: deviation, solid line: average) calculated according to this embodiment approximately coincides with the vertical ground reaction force measured at the force plate. At this time, the correlation coefficient of the two graphs represented by the dotted line of the vertical ground reaction force calculated according to the present embodiment is 0.96.

In the meantime, the second calculating unit 22 calculates the vertical direction (width direction) of the forward direction (longitudinal direction) and the forward direction (horizontal direction) using the calculated vertical ground reaction force GRF _vertical (t) It is possible to calculate the ground reaction force in the longitudinal direction and the width direction of the insole base material, respectively.

Forward direction ground reaction force GRF _ap (t))

Anterior Posterior Ground reaction force GRF _ap (t) can be calculated as shown in the following equation (1-1).

[Mathematical expression 1-1]

GRF _ap (t) = GRF _vertical (t) X tanAP _? (T)

Here, GRF _vertical is the vertical ground repulsion force, AP _θ is the angle between the vector from the right foot to the center of gravity of the body (body) and the vector from the ground toward the vertical direction to the sagittal plane to be.

The AP _? (T) can be expressed by the following equation (1-2).

[Equation 1-2]

,

Here, T is the time (stance phase time) while the foot touches the ground during walking, and the stride = key X 0.415.

The method of calculating the AP _? (T) is as follows.

First, as shown in FIG. 5, as the moment right foot touches the ground AP _θ _min, and when the right foot is that the falling moment of the ground AP _θ _max, the foot right to go to the T time (on the right foot touches the ground rear AP value of _θ for a while falling from the ground for walking time) may appear in the form as shown in FIG. Here, the absolute values of AP _θ _min and AP _θ _max are the same, assuming that the back and forth strides are the same based on the body (body) of ordinary people.

The resulting linear function is

to be.

Where AP _θ _min is the stride / 2 and the key X0.6, the center of gravity of the body,

.

Substituting the AP _&thetas; _min value into the linear function results in [Equation 1-2].

Using this AP _θ (t) and GRF _vertical (t), GRF _ap (t), which is the ground reaction force in the forward direction, can be calculated. It is also possible to apply the same method to the left foot.

FIG. 7 is a graph showing the forward-direction floor surface repulsion force measured using the force plate and the forward-direction floor surface repulsion force calculated according to the present embodiment.

As shown in Fig. 7, it can be seen that the forward direction ground reaction force (dotted line: deviation, solid line: average) calculated according to this embodiment approximately coincides with the forward direction ground reaction force measured in the force plate. The correlation coefficient of the two graphs is 0.98.

Vertical ground reaction force in forward direction ( GRF _ml (t))

The medial lateral ground reaction force GRF _ml (t) in the forward direction, which is the force generated in the lateral direction of the body (body) in the horizontal direction, can be calculated by the following equation (2).

[Mathematical Expression 2-1]

GRF _ml (t) = vertical ground reaction force (GRF _vertical (t)) X tan ML _θ (t)

Here, GRF _vertical (t) is the angle between the vertical ground reaction force is, ML _θ (t) is, as shown in Figure 8, to the body (body), the center of gravity toward the vertical direction from the vector and the ground toward the vector of Is projected onto the frontal plane.

The ML _? (T) can be expressed by the following equation (2-2).

[Equation 2-2]

Here, DS is the time during which two feet are simultaneously touching (Double Support Time), T is the time during which the foot is in contact with the ground during walking (Stance phase time), and DS and T are constants.

The method of calculating the ML _? (T) is as follows.

First, the moment 8, the left foot touches the ground ML _θ _start is called, and when the right foot as the falling time in the left foot is ground to move the beam 1 in the forward ML _θ _end, T time (on the left foot land during contact body (bodies) than the time for falling from the left foot land in a state located in the rear) ML value of _θ may appear in the form as shown in Fig.

Here, assuming that the center of gravity of the body (body) draws a parabolic curve when ordinary people walk, the following parabolic function appears.

The parabola is bilaterally symmetric with respect to the T / 2 value which is half the time (T) taken over one step, and the constants 5 and 4 are determined based on the normal walking.

At a time of T / 2 during normal walking, a constant value of 4 is set because it forms an angle of about 4 degrees between a vector pointing from the toe on the frontal plane to the center of gravity of the body and a vector perpendicular to the ground.

In addition, the moment the foot touches the ground and the moment the foot falls from the ground, it has an angle of about -1 degrees between the vector from the toe on the frontal plane to the center of gravity of the body (body) 4 - (- 1) = 5, the constant 5 is set. The first function of Equation (2-2) is derived using the parabolic function.

However, the ML _θ (t) in a typical walking does not have an exact parabolic shape during the time during which the two feet touch simultaneously (Double Support Time).

When one foot ML _θ (t) is -4 degree, DS 0 seconds when seconds of the time (DS) to the ending point (between 0 seconds ~ DS in seconds) during which both feet are touching the ground at the same time from the moment you touched the ML _θ ( DS). That is, if a function using this value is expressed in the form of the first form of [Equation 2-2], it can be expressed as a second function of Equation 2-2.

As a result, a function from 0 second to DS seconds and from DS seconds to T seconds is a graph for ML _? (T) as shown in FIG. 9 by adding the first function and the second function of Equation (2-2) .

Using this ML _θ (t) and GRF _vertical (t), GRF _ml (t), which is the vertical ground reaction force in the forward direction, can be calculated. It is also possible to apply the same method to the opposite foot.

FIG. 10 is a graph showing vertical ground surface reaction force measured in the forward direction measured by using force plates and vertical ground surface reaction force in the forward direction calculated according to the present embodiment.

As shown in FIG. 10, the vertical ground reaction force (dotted line: deviation, solid line: average) in the forward direction calculated according to the present embodiment is approximately coincident with the vertical ground reaction force measured in the forward direction . The correlation coefficient of the two graphs is 0.84.

As described above, the three-axis (vertical direction, longitudinal direction, and width direction) pressure can be substantially the same as that measured on the force plate by using the values measured by the nine pressure sensors in the vertical direction surface reaction force.

Hereinafter, a method of measuring the ground reaction force using the above foot pressure measuring apparatus will be described.

11 is a flowchart showing a method of measuring a floor reaction force using the foot pressure measuring apparatus of the present invention. 11, in the method of measuring the surface reaction force according to the present invention, the sensor unit 10 provided with the pressure sensor 12 on the insole substrate 11 provided in the above-mentioned insole shape is prepared and worn by the user S10).

At this time, the insole base material 11 is divided into a toe region, a front region, a middle region, and a heel region according to a foot corresponding portion, and the toe region, the middle region, and the heel region are divided into two in the width direction, The full width region is divided into three in the width direction.

Further, the insole base material 11 has a plurality of sensing positions arranged in the longitudinal direction and the width direction.

The pressure sensor 12 is installed at a plurality of sensing positions selected from among the arranged sensing positions.

In this state, the pressure value is measured at the sensing position where the pressure sensor 12 is installed, and at the sensing position where the pressure sensor 12 is not installed, The pressure value is derived using an interpolation method based on the measured pressure value.

Then, the vertical ground reaction force is calculated by summing up the measured pressure values of the respective sensing positions and the derived pressure values (S20).

In this case, the interpolation method is a cubic spline interpolation interpolating using a third order polynomial spline. The cubic spline interpolation is applied to each of the width direction and the longitudinal direction of the insole base material, The pressure value at the sensing position can be calculated.

Then, based on the calculated vertical direction ground reaction force, the horizontal direction ground reaction force including the vertical direction in the forward direction and the forward direction is calculated (S30).

First, the forward direction ground reaction force GRF _ap (t) of the horizontal direction ground reaction force is calculated using the following equations (1-1) and (1-2) (S31).

[Mathematical expression 1-1]

GRF _ap (t) = GRF _vertical (t) X tanAP _? (T)

Where GRF _vertical is the vertical surface repulsion force, AP _θ (t) is the angle between the vector from the right foot to the center of gravity of the body and the vector from the ground to the vertical direction is projected onto the sagittal plane to be.

[Equation 1-2]

,

For example, from the moment your right foot touches the ground, the moment your right foot falls from the ground is 0.8 seconds, the height is 170 cm, and the stride is 70.6 cm,

As shown in Fig.

The forward direction surface reaction force GRF _ap (t) is calculated using the calculated AP _? (T) and the measured GRF _vertical (t) using the equation (1-2) (S32).

The vertical ground reaction force GRF _ml (t) in the forward direction, which is a force generated in the lateral direction of the body among the horizontal ground reaction forces, is calculated using the following equations (2-1) and (2-2) do.

[Mathematical Expression 2-1]

Where GRF _vertical (t) is the vertical ground reaction force, and ML _θ (t) is the angle between the vector from the foot to the center of gravity of the body and the vector from the ground to the vertical direction onto the frontal plane It is an angle.

[Equation 2-2]

For example, if the right foot touched the ground for 0.8 seconds while the two feet were simultaneously touching the ground for 0.12 seconds while walking, the T value is 0.8 and the DS value is 0.12.

Therefore, when applying this to Equation (2-2), the lower formula of Equation (2-2) is applied up to 0.12 seconds, which is the time during which the two feet touch simultaneously from 0 second when the right foot touches the ground , And the upper formula of Equation (2-2) is applied until 0.12 seconds when the two feet touch simultaneously and 0.8 seconds when the right foot falls from the ground.

The vertical ground reaction force GRF _ml (t) in the forward direction is calculated by using ML _? (T) and the measured GRF _vertical (t) derived by using the above expression (2-2).

The above description has been made on the calculation in the order of the ground surface reaction force in the forward direction and the vertical ground reaction force in the forward direction and may be calculated in reverse order.

As described above, it is possible to measure both the ground reaction force in the forward direction and the vertical direction in the forward direction by using the vertical ground reaction force measured in the state in which the sensor unit is worn.

By applying this, it is easy to carry, such as a force plate, without being limited to a place, and it can be applied to various measurement environments.

The scope of the present invention is not limited to the above-described embodiments, but may be embodied in various forms of embodiments within the scope of the appended claims. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the appended claims.

[Description of Reference Numerals]
10: sensor part 11: insole base material
12: Pressure sensor
20: calculating section 21: first calculating section
22: second calculation section

Claims

1. A foot pressure measuring apparatus using floor restraining force,
A sensor unit provided in an insole shape and having a plurality of sensing positions arranged in the longitudinal direction and the width direction and a pressure sensor provided at a plurality of sensing positions selected from the sensing positions; And
The pressure value is measured by the pressure sensor at a sensing position where the pressure sensor is installed and the pressure value is derived based on a pressure value of the pressure sensor by using an interpolation method at a sensing position where the pressure sensor is not located, And a calculation unit for calculating a vertical ground reaction force with a pressure value measured by the interpolation method and a horizontal ground reaction force based on the calculated vertical ground reaction force.

The method according to claim 1,
The interpolation method is a cubic spline interpolation interpolation method.

The method according to claim 1,
The sensor unit includes:
A toe region corresponding to the toe portion and divided into two in the width direction, a front region corresponding to the forefoot region and located behind the toe region and divided into three in the width direction, a heel portion corresponding to the heel, And an insole base member which is located between the front region and the heel region and is divided into a middle region divided into two in a width direction,
Wherein the pressure sensor is installed in each of the divided portions of the divided region of the insole base material.

The method of claim 3,
And the pressure sensor located at the divided portion in the same area is provided so as to be positioned in a straight line in the width direction.

The method according to claim 1,
The forward direction ground reaction force GRF _ap (t) of the horizontal direction ground reaction force,
GRF _ap (t) = GRF _vertical (t) X tanAP _[theta] (t),

,
GRF _vertical (t): vertical ground reaction force,
AP _θ (t): angle between the vector from the foot to the center of gravity of the body and the vector from the ground to the vertical direction,
T: Stance phase time while the foot touches the ground during walking,
Stride = Key X 0.415
Foot pressure measuring device.

The method according to claim 1,
The ground surface reaction force GRF _ml (t) in the direction perpendicular to the advancing direction of the horizontal direction ground reaction force,
GRF _ml (t) = GRF _vertical (t) X tan ML _? (T),

,
GRF _vertical (t): vertical ground reaction force,
ML _θ (t): The angle between the vector from the foot to the center of gravity of the body and the vector from the ground to the vertical direction is projected onto the frontal plane,
DS: double support time during walking,
T: Stance phase time while the foot touches the ground during walking
Foot pressure measuring device.

Preparing a sensor unit provided in an insole shape and having a plurality of sensing positions arranged in the longitudinal direction and the width direction and having a pressure sensor at a plurality of sensing positions selected from the sensing positions;
A pressure value is measured at a sensing position where the pressure sensor is installed through a pressure sensor of the sensor unit when the sensor unit is worn while wearing the sensor unit and a pressure value is calculated using an interpolation method set at a sensing position where the pressure sensor is not installed Calculating a vertical ground reaction force with a pressure value measured by the pressure sensor and a pressure value derived by the interpolation method; And
And calculating a horizontal ground reaction force on the basis of the vertical ground reaction force.

8. The method of claim 7,
Wherein the interpolation method is a method of measuring a ground reaction force using a foot pressure measuring device using cubic spline interpolation interpolation.

8. The method of claim 7,
The forward direction ground reaction force GRF _ap (t) of the horizontal direction ground reaction force is
GRF _ap (t) = GRF _vertical (t) X tanAP _θ (t)
here,

,
GRF _vertical (t): vertical ground reaction force,
AP _θ (t): Angle between the vector from the foot to the center of gravity of the body and the vector from the ground to the vertical direction is projected onto the sagittal plane,
T: Stance phase time while the foot touches the ground during walking,
Stride = Key X 0.415
Measurement method of ground reaction force using foot pressure measuring device.

8. The method of claim 7,
GRF _ml (t) = GRF _vertical (t) X tan ML _θ (t) is used to calculate the ground reaction force GRF _ml (t) in the direction perpendicular to the advancing direction of the horizontal direction ground reaction force,
here,

,
GRF _vertical (t): vertical ground reaction force,
ML _θ (t): The angle between the vector from the foot to the center of gravity of the body and the vector from the ground to the vertical direction is projected onto the frontal plane,
DS: double support time during walking,
T: Stance phase time while the foot touches the ground during walking
Measurement method of ground reaction force using foot pressure measuring device.